syncope

Syncope

MRS SHAGUFTA ISHTIAQRESPIRATORY AND CIRTICAL CARE TECHNOLOGIST.

DIMT-Dow University of Health Sciences

OBJECTIVES

AT THE END OF LECTURE STUDENTS WILL BE ABLE TO

Understand syncope

Know Etiology of syncope

Know the Impact of syncope

Classification of Transient Loss of Consciousness (TLOC)

Syncope• Neurally-mediated reflex

syndromes

• Orthostatic hypotension

• Cardiac arrhythmias

• Structural cardiovascular disease

Disorders Mimicking Syncope• With loss of consciousness, i.e.,

seizure disorders

• Without loss of consciousness, i.e., psychogenic “pseudo-syncope”

Real or Apparent Transient Loss of Syncope (TLOC)

Brignole M, et al. Europace, 2004;6:467-537.

Syncope – A Symptom, Not a Diagnosis

Self-limited loss of consciousness and postural tone

Relatively rapid onset

Variable warning symptoms

Spontaneous, complete, and usually prompt recovery without medical or surgical intervention

Underlying mechanism is transient global cerebral hypoperfusion.


Section I

Causes of True Syncope

Orthostatic CardiacArrhythmia

StructuralCardio-

Pulmonary

1• Vasovagal

syncope (VVS)

• Carotid sinus syndrome (CSS)

• SituationalCoughPost- Micturition

2• Drug-Induced• Autonomic

Nervous System (ANS) Failure

3• Brady

Sinus Node Dysfunction

Atro Ventricular Block

• TachyVent

Tacycardia VT

Sinus VT (SVT)

• Long QT Syndrome

4 • Acute

Myocardial Ischemia

• Aortic Stenosis

• Hypertrophic Cardiomyopathy (HCM)

• Pulmonary Hypertension

• Aortic Dissection

Neurally-Mediated

Section II:

Diagnosis

Diagnostic Objectives

Distinguish true syncope from syncope mimics

Determine presence of heart disease

Establish the cause of syncope with sufficient

• Assessment of prognosis

• effective preventive treatment

A Diagnostic Plan is Essential

Initial Examination• Detailed patient history• Physical exam• ECG• Supine and upright

blood pressure Monitoring

• Holter• Event• Insertable Loop Recorder (ILR)

Cardiac Imaging Special Investigations

• Head-up tilt test• Hemodynamics • Electrophysiology study

Diagnostic Flow Diagram for Transient Loss of Consiousness TLOC

Initial Evaluation

Treatment

Syncope Not Syncope

Certain Diagnosis

Unexplained Syncope

Cardiac Likely

Cardiac Tests

Neurally-Mediated or Orthostatic Likely

Tests for Neurally-Mediated Syncope

Frequent or Severe Episodes

Tests for Neurally-Mediated Syncope

Single/Rare Episodes

No Further Evaluation

Confirm with Specific Test or

Specialist Consultation

Suspected Diagnosis

+ - + - + -

Treatment Treatment

Re-AppraisalRe-Appraisal

Treatment

Initial Exam: Detailed Patient History

Circumstances of recent event• Eyewitness • Symptoms at onset of event• Sequelae• Medications

Circumstances of more remote events

Concomitant disease, especially cardiac

Pertinent family history• Cardiac disease• Sudden death• Metabolic disorders

Past medical history• Neurological history• Syncope


Initial Exam: Thorough Physical

Vital signs

• Heart rate

• Orthostatic blood pressure change

Cardiovascular exam: Is heart disease present?

• ECG: Long QT, pre-excitation, conduction system disease

• Echo: LV function, valve status, HCM—Hypertrophic Cardiomyopathy

Neurological exam

Carotid sinus massage

• Perform under clinically appropriate conditions preferably during head-up tilt test

• Monitor both ECG and BP


Carotid Sinus Massage (CSM)

Method1

• Massage, 5-10 seconds

• Don’t occlude

• Supine and upright posture (on tilt table)

Outcome

• 3 second as ystole and/or 50 mmHg fall in systolic BP with reproduction of symptoms = Carotid Sinus Syndrome

Absolute contraindications2

• Carotid bruit, known significant carotid arterial disease, previous CVA, MI last 3 months

Complications

• Primarily neurological

• Less than 0.2%

• Usually transient

60° - 80°

Other Diagnostic Tests

Ambulatory ECG

• Holter monitoring

• Event recorder− Intermittent vs. Loop

− Insertable Loop Recorder (ILR)

Head-Up Tilt (HUT)

• Includes drug provocation (NTG, isoproterenol)

• Carotid Sinus Massage (CSM)

Adenosine Triphosphate Test (ATP)

Electrophysiology Study (EPS)


Heart Monitoring Options

ILR

Event Recorders(non-lead and loop)

Holter Monitor

12-Lead

2 Days

7-30 Days

Up to 14 Months

10 Seconds

OPTION

TIME (Months)

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14


Head-Up Tilt Test (HUT)

Protocols vary

Useful as diagnostic adjunct in atypical syncope cases

Useful in teaching patients to recognize prodromal symptoms

Not useful in assessing treatment

Brignole M, et al. Europace. 2004;6:467-537.

60° - 80°

Reveal® Plus ILR

Insertable Loop Recorder (ILR)

Typical Location of theReveal® Plus ILR

Click once on black screen to play video.

Insertable Loop Recorder (ILR)

The ILR is an implantable patient – and automatically – activated monitoring system that records subcutaneous ECG and is indicated for: Patients with clinical syndromes or situations at increased risk of

cardiac arrhythmias

Patients who experience transient symptoms that may suggest a cardiac arrhythmia

Section III:

Specific Conditions and Treatment

Specific Conditions

Cardiac arrhythmia

• Brady/Tachy

• Long QT syndrome

• Torsade de pointes

• Brugada

• Drug-induced

Structural cardio-pulmonary

Neurally-mediated

• Vasovagal Syncope (VVS)

• Carotid Sinus Syndrome (CSS)

Orthostatic

Cardiac Syncope

Includes cardiac arrhythmias

Often life-threatening

May be warning of critical CV disease

• Tachy and brady arrhythmias

• Myocardial ischemia, aortic stenosis, pulmonary hypertension, aortic dissection

Assess culprit arrhythmia or structural abnormality aggressively

Initiate treatment promptly


Syncope Due to Structural Cardiovascular Disease: Principle Mechanisms

Acute MI/Ischemia

• 2° neural reflex bradycardia – Vasodilatation, arrhythmias, low output (rare)

Hypertrophic cardiomyopathy

• Limited output during exertion (increased obstruction, greater demand), arrhythmias, neural reflex

Acute aortic dissection

• Neural reflex mechanism, pericardial tamponade

Pulmonary embolus/pulmonary hypertension

• Neural reflex, inadequate flow with exertion

Valvular abnormalities

• Aortic stenosis – Limited output, neural reflex dilation in periphery

• Mitral stenosis, atrial myxoma – Obstruction to adequate flow


Syncope Due to Cardiac Arrhythmias

Bradyarrhythmias

• Sinus arrest, exit block

• High grade or acute complete AV block

• Can be accompanied by vasodilatation (VVS, CSS)

Tachyarrhythmias

• Atrial fibrillation/flutter with rapid ventricular rate (eg, pre-excitation syndrome)

• Paroxysmal SVT or VT

• Torsade de pointes


Cardiac Rhythms During Unexplained Syncope-ILR

Seidl K. Europace. 2000;2(3):256-262.Krahn AD. PACE. 2002;25:37-41.Medtronic ILR Replacement Data. FY03, 04. On file.

No Recurrence 36%

(31-48%)

Normal Sinus Rhythm 31%

(17-44%)

Other 11%

Arrhythmia 22%

(13-32%)

Tachycardia 6%(2-11%)

Bradycardia 16%

(11-21%)

Composite: N=133 to 7109

Long QT Syndromes

Mechanism

• Abnormalities of sodium and/or potassium channels

• Susceptibility to polymorphic VT (Torsade de pointes)

Prevalence

• Drug-induced forms – Common

• Genetic forms – Relatively rare, but increasingly being recognized

• “Concealed” forms:

− May be common

− Provide basis for drug-induced torsade

Schwartz P, Priori S. In: Zipes D and Jalife J, eds. Cardiac Electrophysiology. Saunders;2004:651-659.

Syncope: Torsade de Pointes

From the files of DG Benditt, MD. U of M Cardiac Arrhythmia Center

Long QT Syndromes: 12-Lead ECG

From the files of DG Benditt, MD. U of M Cardiac Arrhythmia Center

Drug-Induced QT Prolongation(List is continuously being updated)

Antiarrhythmics

• Class IA

• Class III

Antianginal Agents Psychoactive Agents

Antibiotics

• Erythromycin, Pentamidine, Fluconazole, Ciprofloxacin and its relatives

Nonsedating antihistamines

• Terfenadine*, Astemizole

Others

• Cisapride*, Droperidol, Haloperidol

*Removed from U.S. MarketBrignole M, et al. Europace, 2004;6:467-537.

Syncope Due to Bradyarrhythmia

ACC/AHA/NASPE 2002 Guideline Update. Circ. 2002;106:2145-2161.

nV

0.4

0.2

0.0

-0.2

-0.4

:45:44:43:42:41:40:39:38:37

:37:36:35:34:33:32:31:30:29

:29:28:27:26:25:24:23:22:21

08:23:21

8:23:29

08:23:37

0.4

0.2

0.0

-0.2

-0.4

0.4

0.2

0.0

-0.2

-0.4

Treatment of Syncope Due to Tachyarrhythmia

Atrial tachyarrhythmias

• AVRT due to accessory pathway – Ablate pathway

• AVNRT – Ablate AV nodal slow pathway

• Atrial fib – Pacing, linear/focal ablation for paroxysmal AF

• Atrial flutter – Ablate the IVC-TV isthmus of the re-entrant circuit for ‘typical’ flutter

Ventricular tachyarrhythmias

• Ventricular tachycardia – ICD or ablation where appropriate

• Torsade de pointes – Withdraw offending drug or implant ICD (long QT/Brugada/short QT)

Drug therapy may be an alternative in many cases


Neurally-Mediated Reflex Syncope

Vasovagal Syncope (VVS)

Carotid Sinus Syndrome (CSS)

Situational syncope

• Post-micturition

• Cough

• Swallow

• Defecation

• Blood drawing, etc.


VVSDiagnosis

History and physical exam, ECG and BP

Head-Up Tilt (HUT) – Protocol:

• Fast > 2 hours

• ECG and continuous blood pressure, supine, and upright

• Tilt to 70°, 20 minutes

• Isoproterenol/Nitroglycerin if necessary

• End point – Loss of consciousness

60° - 80°

Benditt D, et al. JACC. 1996;28:263-275.Brignole M, et al. Europace, 2004;6:467-537.

VVS General Treatment Measures

Optimal treatment strategies for VVS are a source of debate

Treatment goals• Acute intervention

− Physical maneuvers, eg, crossing legs or tugging arms

− Lowering head− Lying down

Long-term prevention• Tilt training

• Education

• Diet, fluids, salt

• Support hose

• Drug therapy

• Pacing


VVS Tilt Training Protocol

Objectives

• Enhance orthostatic tolerance

• Diminish excessive autonomic reflex activity

• Reduce syncope susceptibility/recurrences

Technique

• Prescribed periods of upright posture against a wall

• Start with 3-5 min BID

• Increase by 5 min each week until a duration of 30 min is achieved

Reybrouck T, et al. PACE. 2000;23(4 Pt. 1):493-498.

CSSEtiology

Sensory nerve endings in the carotid sinus walls respond to deformation

“Deafferentation” of neck muscles may contribute

Increased afferent signals tobrain stem

Reflex increase in efferent vagal activity and diminution of sympathetic tone results in bradycardia and vasodilatation

Carotid Sinus

Orthostatic Hypotension

Etiology

Drug-induced (very common)

• Diuretics

• Vasodilators

Primary autonomic failure

• Multiple system atrophy

• Parkinson’s Disease

• Postural Orthostatic Tachycardia Syndrome (POTS)

Secondary autonomic failure

• Diabetes

• Alcohol

• Amyloid


Syncope: Diagnostic Testing in Hospital Strongly Recommended

Suspected/known ‘significant’ heart disease

ECG abnormalities suggesting potential life-threatening arrhythmic cause

Syncope during exercise

Severe injury or accident

Family history of premature sudden death


Conclusion

Syncope is a common symptom with many causes

Deserves thorough investigation and appropriate treatment

A disciplined approach is essential


Brief Statement

Indications9526 Reveal® Plus Insertable Loop RecorderThe Reveal Plus ILR is an implantable patient- and automatically activated monitoring system that records subcutaneous ECG and is indicated forPatients with clinical syndromes or situations at increased risk of cardiac arrhythmias Patients who experience transient symptoms that may suggest a cardiac arrhythmia 6191 ActivatorThe Model 6191 Activator is intended for use in combination with a Medtronic Model 9526 Reveal Plus Insertable Loop Recorder.ContraindicationsThere are no known contraindications for the implantation of the Reveal Plus ILR. However, the patient’s particular medical condition may dictate whether or not a subcutaneous, chronically implanted device can be tolerated.Warnings/Precautions9526 Reveal Plus Insertable Loop RecorderPatients with the Reveal Plus ILR should avoid sources of magnetic resonance imaging, diathermy, high sources of radiation, electrosurgical cautery, external defibrillation, lithotripsy, and radiofrequency ablation to avoid electrical reset of the device, and/or inappropriate sensing.6191 ActivatorOperation of the Model 6191 Activator near sources of electromagnetic interference, such as cellular phones, computer monitors, etc., may adversely affect the performance of this device.Potential ComplicationsPotential complications include, but are not limited to, body tissue rejection phenomena, including local tissue reaction, infection, device migration and erosion of the device through the skin.2090 ProgrammerThe Medtronic/Vitatron CareLink programmer system is comprised of prescription devices indicated for use in the interrogation and programming of implantable medical devices. Prior to use, refer to the Programmer Reference Guide as well as the appropriate programmer software and implantable device technical manuals for more information related to specific implantable device models. Programming should be attempted only by appropriately trained personnel after careful study of the technical manual for the implantable device and after careful determination of appropriate parameter values based on the patient's condition and pacing system used. The Medtronic/Vitatron CareLink programmer must be used only for programming implantable devices manufactured by Medtronic or Vitatron.See the device manual for detailed information regarding the implant procedure, indications, contraindications, warnings, precautions, and potential complications/adverse events. For further information, please call Medtronic at 1-800-328-2518 and/or consult Medtronic’s website at www.medtronic.com. To learn more about syncope, visit www.fainting.com.Caution: Federal law (USA) restricts this device to sale by or on the order of a physician.

http://www.medtronic.com/

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